You randomly sample 5 people in your school and none of them is a vegetarian. Does this mean that the probability of being a vegetarian for students at your school equal 0? Explain.
a. Yes. Since no vegetarians were found during the survey the probability is 0. If at a later point, vegetarians are found, this will increase the probability.
b. No. Probability is subjective, surveyor decides probability should be greater than 0, then they can make that way.
c. No. In the short run, the proportion of a given outcome can flucutate a lot. As more people are sampled, the proportion should approach the real probability.
2. Over the last 10 years, the average number of deaths due to accidents involving a certain commercial airline has been about 23 per year. Over the same period, the average number of passengers of the airlines has been more than 5.4 million per year.
a. Can this be considered a long/short run of trails? Explain.
It can be a short run because the number of trials is sufficiently large.
It can be a short run because the number of trials is small.
It can be a long run because the number of trials is sufficiently large.
It can be a short run because the number of trials is small.
b. Estimate the probability of dying on a particular flight.
c. The last fatal accident involving the airline occured more than two years ago. Mary comments that she's afraid of flying because airlines are "due for an accident". Comment.